@rem mysqldump --user=username --password=password databasename > out file
@rem ex:
@set dt=%date:~0%
@rem mysqldump --user=caifeifei --password=112997 class1_1 > class1_1.%date:~0, 10%.%time:~0:5%.sql
@set param=%1
@mysqldump --user=caifeifei --password=112997 class1_1 > "class1_1.%date:~0, 10%.%time:~0, 2%-%time:~3, 2%_%param:~1%.sql"